in a roasting pan put some oxtail (they usually come in slices/pieces), some other fatty beef - I don't know what the cut would be called in north america. Here it's soup meat and looks like some short ribs with a ton of extra meet attached in a rectangle shape - chopped celery root, carrots, onions, a little salt, some leek if you like..the veggies are pretty open here.

Bake it until everything is caramelized and brownish. Stir every once in a while to coat the veggies in the fat from the oxtail so that they roast very nicely. When it's finished and the meat is nice and soft, separate it from the bones and serve in a pile.

I've made this and used the extra leftover fat to roast potatoes which were incredible but not very paleo.

Oxtail soup is the same ingredients
-Oxtails+other beef, doesn't have to be fatty
-celery root
-leek
-bay leaves, preferably fresh
-carrots
-parsley, preferably fresh
optional: extra bones/leftover carcases from dinners.. if you have a lot of bones add a tad of vinegar to the soup to help get the good stuff out. You can also add a few dried chilies for bite

I generally leave the veggies whole or in a few large pieces and fish them out later and either toss them or make them into a mash with butter.

Put the ingredients in a pot of cold water. Let it sit for a while and very gently/slowly warm it, keep it to barely a simmer and do it all day - overnight too if you can. Fish out the veggies and either chop and put back in or discard or eat as a mash, separate meat from bone and fat and stick the meat back in the soup. Put some chopped parsley in it and simmer again for a while. Add salt and pepper to taste - depending on the meat you might need a tsp. of boullion powder.. however the flavour REALLY intensifies as you leave this soup to sit in the fridge.